A system may include an array of sensor elements, the array of sensor elements each comprising a first type of passive reactive element, a second type of passive reactive element electrically coupled to the array of sensor elements, a driver configured to drive the array of sensor elements and the second type of passive reactive element, and control circuitry configured to control enabling and disabling of individual sensor elements of the array of sensor elements to ensure no more than one of the array of sensor elements is enabled at a time such that when one of the array of sensor elements is enabled, the one of the array of sensor elements and the second type of passive reactive element together operate as a resonant sensor.

A pipeline AC mitigation SSD Marker Station has a shape and land surface area footprint that are similar to conventional pipeline location markers or corrosion test stations. The SSD Marker Station includes an SSD device that connects an underground metallic pipeline to an underground grounding conductor. The SSD Marker Station further includes a disconnect switch configured to disconnect the SSD device from the pipeline and/or grounding conductor. Also included is a pair of testing ports that are in electrical communication with the SSD device. Testing of the SSD device thereby requires only operating the disconnect switch to isolate the SSD device from the pipeline and/or grounding connector and performing an electrical measurement across the testing ports. In embodiments, the SSD Marker Station meets all requirements applicable to a pipeline location marker, and can be installed in lieu of a pipeline location marker.

A system may include a resistive-inductive-capacitive sensor, a driver configured to drive the resistive-inductive-capacitive sensor at a driving frequency, and a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to determine a measured change in a resonant frequency of the resistive-inductive-capacitive sensor and based on the measured change, modify the driving frequency.

A system may include a resistive-inductive-capacitive sensor, a driver configured to drive the resistive-inductive-capacitive sensor at a driving frequency, and a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to determine a measured change in a resonant frequency of the resistive-inductive-capacitive sensor and based on the measured change, modify the driving frequency.

A method determines scattering parameters, S-parameters, for a device under test for a first frequency range. The method includes receiving S-parameters for the device under test for a second frequency range, the second frequency range greater than the first frequency range. Generally, the S-parameters for the device under test for the second frequency range can be determined using known methods. The method further includes measuring an actual response of the device under test, determining a desired signal of the device under test, and determining the S-parameters for the device under test for the first frequency range based the S-parameters for the second frequency range, actual response of the device under test and the desired signal of the device under test.

A method for examining differential pair transmission lines, performed by a processor, comprising: capturing a plurality of first insertion losses of a first signal line within a frequency range and a plurality of second insertion losses of a second signal line within the frequency range, wherein the first signal line and the second signal line are configured to transmit a pair of differential signals; calculating a plurality of maximum error ratios between the first insertion losses and the second insertion losses within the frequency range; determining whether any one of the maximum error ratios is greater than or equal to an upper threshold; outputting a warning signal when the processor determines one of the maximum error ratios is greater than or equal to the upper threshold; and ending the method when the processor determines each one of the maximum error ratios is smaller than the upper threshold.

A method for examining differential pair transmission lines, performed by a processor, comprising: capturing a plurality of first insertion losses of a first signal line within a frequency range and a plurality of second insertion losses of a second signal line within the frequency range, wherein the first signal line and the second signal line are configured to transmit a pair of differential signals; calculating a plurality of maximum error ratios between the first insertion losses and the second insertion losses within the frequency range; determining whether any one of the maximum error ratios is greater than or equal to an upper threshold; outputting a warning signal when the processor determines one of the maximum error ratios is greater than or equal to the upper threshold; and ending the method when the processor determines each one of the maximum error ratios is smaller than the upper threshold.

A vector network analyzer is provided which includes a first measuring port, a digital interface connected to the first measuring port, a second measuring port adapted to be connected to a radio frequency (RF) input or output of a device under test (DUT), and a processor. The digital interface is adapted to be connected to a digital input or output of the DUT. The processor is adapted to determine scattering parameters (S-parameters) of the DUT based on measuring signals transmitted to the DUT and received from the DUT by the first measuring port and the second measuring port.

A vector network analyzer is provided which includes a first measuring port, a digital interface connected to the first measuring port, a second measuring port adapted to be connected to a radio frequency (RF) input or output of a device under test (DUT), and a processor. The digital interface is adapted to be connected to a digital input or output of the DUT. The processor is adapted to determine scattering parameters (S-parameters) of the DUT based on measuring signals transmitted to the DUT and received from the DUT by the first measuring port and the second measuring port.

An apparatus has at least substrate having at least two conductive paths, a least two connectors positioned in a first plane, and a movable stage connected to one of the at least one substrate to move the one substrate perpendicular to the first plane form an electrically conductive path between two of the at least two connectors.